UseDefaultTag for skip build if not default branch.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

cmd/drone-docker/main.go

@@ -246,11 +246,19 @@ func run(c *cli.Context) error {
 	}
 
 	if c.Bool("tags.auto") {
-		plugin.Build.Tags = docker.DefaultTagSuffix(
+		if docker.UseDefaultTag( // return true if not default branch, or not tag
 			c.String("commit.ref"),
 			c.String("repo.branch"),
-			c.String("tags.suffix"),
-		)
+		) {
+			plugin.Build.Tags = docker.DefaultTagSuffix(
+				c.String("commit.ref"),
+				c.String("tags.suffix"),
+			)
+		} else {
+			logrus.Printf("skipping automated docker build for %s", c.String("commit.ref"))
+
+			return nil
+		}
 	}
 
 	return plugin.Exec()

docker.go

@@ -61,6 +61,24 @@ type (
 	}
 )
 
+func stripHeadPrefix(ref string) string {
+	ref = strings.TrimPrefix(ref, "refs/heads/")
+	return ref
+}
+
+// UseDefaultTag for keep only default branch for latest tag
+func UseDefaultTag(ref, defaultBranch string) bool {
+	if strings.HasPrefix(ref, "refs/tags/") {
+		return true
+	}
+
+	if stripHeadPrefix(ref) == defaultBranch {
+		return true
+	}
+
+	return false
+}
+
 // Exec executes the plugin step
 func (p Plugin) Exec() error {
 	// start the Docker daemon server

docker_test.go

@@ -0,0 +1,25 @@
+package docker
+
+import "testing"
+
+func Test_stripHeadPrefix(t *testing.T) {
+	type args struct {
+		ref string
+	}
+	tests := []struct {
+		args args
+		want string
+	}{
+		{
+			args: args{
+				ref: "refs/heads/master",
+			},
+			want: "master",
+		},
+	}
+	for _, tt := range tests {
+		if got := stripHeadPrefix(tt.args.ref); got != tt.want {
+			t.Errorf("stripHeadPrefix() = %v, want %v", got, tt.want)
+		}
+	}
+}

tags.go

@@ -9,8 +9,8 @@ import (
 
 // DefaultTagSuffix returns a set of default suggested tags
 // based on the commit ref with an attached suffix.
-func DefaultTagSuffix(ref, defaultBranch, suffix string) []string {
-	tags := DefaultTags(ref, defaultBranch)
+func DefaultTagSuffix(ref, suffix string) []string {
+	tags := DefaultTags(ref)
 	if len(suffix) == 0 {
 		return tags
 	}
@@ -26,18 +26,10 @@ func DefaultTagSuffix(ref, defaultBranch, suffix string) []string {
 
 // DefaultTags returns a set of default suggested tags based on
 // the commit ref.
-func DefaultTags(ref, defaultBranch string) []string {
-
-	if defaultBranch != "" && strings.HasPrefix(ref, "refs/heads/") {
-		if stripHeadPrefix(ref) != defaultBranch {
-			return []string{}
-		}
-	}
-
+func DefaultTags(ref string) []string {
 	if !strings.HasPrefix(ref, "refs/tags/") {
 		return []string{"latest"}
 	}
-
 	v := stripTagPrefix(ref)
 	version, err := semver.NewVersion(v)
 	if err != nil {
@@ -66,8 +58,3 @@ func stripTagPrefix(ref string) string {
 	ref = strings.TrimPrefix(ref, "v")
 	return ref
 }
-
-func stripHeadPrefix(ref string) string {
-	ref = strings.TrimPrefix(ref, "refs/heads/")
-	return ref
-}

tags_test.go

@@ -25,29 +25,23 @@ func Test_stripTagPrefix(t *testing.T) {
 
 func TestDefaultTags(t *testing.T) {
 	var tests = []struct {
-		Before        string
-		DefaultBranch string
-		After         []string
+		Before string
+		After  []string
 	}{
-		{"", "master", []string{"latest"}},
-		{"refs/heads/master", "master", []string{"latest"}},
-		{"refs/tags/0.9.0", "master", []string{"0.9", "0.9.0"}},
-		{"refs/tags/1.0.0", "master", []string{"1", "1.0", "1.0.0"}},
-		{"refs/tags/v1.0.0", "master", []string{"1", "1.0", "1.0.0"}},
-		{"refs/tags/v1.0.0-alpha.1", "master", []string{"1.0.0-alpha.1"}},
+		{"", []string{"latest"}},
+		{"refs/heads/master", []string{"latest"}},
+		{"refs/tags/0.9.0", []string{"0.9", "0.9.0"}},
+		{"refs/tags/1.0.0", []string{"1", "1.0", "1.0.0"}},
+		{"refs/tags/v1.0.0", []string{"1", "1.0", "1.0.0"}},
+		{"refs/tags/v1.0.0-alpha.1", []string{"1.0.0-alpha.1"}},
 
 		// malformed or errors
-		{"refs/tags/x1.0.0", "master", []string{"latest"}},
-		{"v1.0.0", "master", []string{"latest"}},
-
-		// defualt branch
-		{"refs/heads/master", "master", []string{"latest"}},
-		{"refs/heads/test", "master", []string{}},
-		{"refs/tags/v1.0.0", "master", []string{"1", "1.0", "1.0.0"}},
+		{"refs/tags/x1.0.0", []string{"latest"}},
+		{"v1.0.0", []string{"latest"}},
 	}
 
 	for _, test := range tests {
-		got, want := DefaultTags(test.Before, test.DefaultBranch), test.After
+		got, want := DefaultTags(test.Before), test.After
 		if !reflect.DeepEqual(got, want) {
 			t.Errorf("Got tag %v, want %v", got, want)
 		}
@@ -56,19 +50,16 @@ func TestDefaultTags(t *testing.T) {
 
 func TestDefaultTagSuffix(t *testing.T) {
 	var tests = []struct {
-		Before        string
-		DefaultBranch string
-		Suffix        string
-		After         []string
+		Before string
+		Suffix string
+		After  []string
 	}{
 		// without suffix
 		{
-			After:         []string{"latest"},
-			DefaultBranch: "",
+			After: []string{"latest"},
 		},
 		{
-			Before:        "refs/tags/v1.0.0",
-			DefaultBranch: "",
+			Before: "refs/tags/v1.0.0",
 			After: []string{
 				"1",
 				"1.0",
@@ -77,14 +68,12 @@ func TestDefaultTagSuffix(t *testing.T) {
 		},
 		// with suffix
 		{
-			DefaultBranch: "",
-			Suffix:        "linux-amd64",
-			After:         []string{"linux-amd64"},
+			Suffix: "linux-amd64",
+			After:  []string{"linux-amd64"},
 		},
 		{
-			DefaultBranch: "",
-			Before:        "refs/tags/v1.0.0",
-			Suffix:        "linux-amd64",
+			Before: "refs/tags/v1.0.0",
+			Suffix: "linux-amd64",
 			After: []string{
 				"1-linux-amd64",
 				"1.0-linux-amd64",
@@ -92,14 +81,12 @@ func TestDefaultTagSuffix(t *testing.T) {
 			},
 		},
 		{
-			DefaultBranch: "",
-			Suffix:        "nanoserver",
-			After:         []string{"nanoserver"},
+			Suffix: "nanoserver",
+			After:  []string{"nanoserver"},
 		},
 		{
-			DefaultBranch: "",
-			Before:        "refs/tags/v1.9.2",
-			Suffix:        "nanoserver",
+			Before: "refs/tags/v1.9.2",
+			Suffix: "nanoserver",
 			After: []string{
 				"1-nanoserver",
 				"1.9-nanoserver",
@@ -109,31 +96,9 @@ func TestDefaultTagSuffix(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		got, want := DefaultTagSuffix(test.Before, test.DefaultBranch, test.Suffix), test.After
+		got, want := DefaultTagSuffix(test.Before, test.Suffix), test.After
 		if !reflect.DeepEqual(got, want) {
 			t.Errorf("Got tag %v, want %v", got, want)
 		}
 	}
 }
-
-func Test_stripHeadPrefix(t *testing.T) {
-	type args struct {
-		ref string
-	}
-	tests := []struct {
-		args args
-		want string
-	}{
-		{
-			args: args{
-				ref: "refs/heads/master",
-			},
-			want: "master",
-		},
-	}
-	for _, tt := range tests {
-		if got := stripHeadPrefix(tt.args.ref); got != tt.want {
-			t.Errorf("stripHeadPrefix() = %v, want %v", got, tt.want)
-		}
-	}
-}